Re: [PATCH] mtip32xx: dynamically allocate buffer in debugfs functions

From: Asai Thambi S P
Date: Fri Jul 12 2013 - 18:59:23 EST


On 5/23/2013 2:23 PM, David Milburn wrote:

> Dynamically allocate buf to prevent warnings:
>
> drivers/block/mtip32xx/mtip32xx.c: In function âmtip_hw_read_device_statusâ:
> drivers/block/mtip32xx/mtip32xx.c:2823: warning: the frame size of 1056 bytes is larger than 1024 bytes
> drivers/block/mtip32xx/mtip32xx.c: In function âmtip_hw_read_registersâ:
> drivers/block/mtip32xx/mtip32xx.c:2894: warning: the frame size of 1056 bytes is larger than 1024 bytes
> drivers/block/mtip32xx/mtip32xx.c: In function âmtip_hw_read_flagsâ:
> drivers/block/mtip32xx/mtip32xx.c:2917: warning: the frame size of 1056 bytes is larger than 1024 bytes
>
> Signed-off-by: David Milburn <dmilburn@xxxxxxxxxx>


Acked-by: Asai Thambi S P <asamymuthupa@xxxxxxxxxx>

> ---
> drivers/block/mtip32xx/mtip32xx.c | 47 +++++++++++++++++++++++++++++--------
> 1 files changed, 37 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
> index 847107e..baa0996 100644
> --- a/drivers/block/mtip32xx/mtip32xx.c
> +++ b/drivers/block/mtip32xx/mtip32xx.c
> @@ -2806,34 +2806,51 @@ static ssize_t show_device_status(struct device_driver *drv, char *buf)
> static ssize_t mtip_hw_read_device_status(struct file *f, char __user *ubuf,
> size_t len, loff_t *offset)
> {
> + struct driver_data *dd = (struct driver_data *)f->private_data;
> int size = *offset;
> - char buf[MTIP_DFS_MAX_BUF_SIZE];
> + char *buf;
> + int rv = 0;
>
> if (!len || *offset)
> return 0;
>
> + buf = kzalloc(MTIP_DFS_MAX_BUF_SIZE, GFP_KERNEL);
> + if (!buf) {
> + dev_err(&dd->pdev->dev,
> + "Memory allocation: status buffer\n");
> + return -ENOMEM;
> + }
> +
> size += show_device_status(NULL, buf);
>
> *offset = size <= len ? size : len;
> size = copy_to_user(ubuf, buf, *offset);
> if (size)
> - return -EFAULT;
> + rv = -EFAULT;
>
> - return *offset;
> + kfree(buf);
> + return rv ? rv : *offset;
> }
>
> static ssize_t mtip_hw_read_registers(struct file *f, char __user *ubuf,
> size_t len, loff_t *offset)
> {
> struct driver_data *dd = (struct driver_data *)f->private_data;
> - char buf[MTIP_DFS_MAX_BUF_SIZE];
> + char *buf;
> u32 group_allocated;
> int size = *offset;
> - int n;
> + int n, rv = 0;
>
> if (!len || size)
> return 0;
>
> + buf = kzalloc(MTIP_DFS_MAX_BUF_SIZE, GFP_KERNEL);
> + if (!buf) {
> + dev_err(&dd->pdev->dev,
> + "Memory allocation: register buffer\n");
> + return -ENOMEM;
> + }
> +
> size += sprintf(&buf[size], "H/ S ACTive : [ 0x");
>
> for (n = dd->slot_groups-1; n >= 0; n--)
> @@ -2888,21 +2905,30 @@ static ssize_t mtip_hw_read_registers(struct file *f, char __user *ubuf,
> *offset = size <= len ? size : len;
> size = copy_to_user(ubuf, buf, *offset);
> if (size)
> - return -EFAULT;
> + rv = -EFAULT;
>
> - return *offset;
> + kfree(buf);
> + return rv ? rv : *offset;
> }
>
> static ssize_t mtip_hw_read_flags(struct file *f, char __user *ubuf,
> size_t len, loff_t *offset)
> {
> struct driver_data *dd = (struct driver_data *)f->private_data;
> - char buf[MTIP_DFS_MAX_BUF_SIZE];
> + char *buf;
> int size = *offset;
> + int rv = 0;
>
> if (!len || size)
> return 0;
>
> + buf = kzalloc(MTIP_DFS_MAX_BUF_SIZE, GFP_KERNEL);
> + if (!buf) {
> + dev_err(&dd->pdev->dev,
> + "Memory allocation: flag buffer\n");
> + return -ENOMEM;
> + }
> +
> size += sprintf(&buf[size], "Flag-port : [ %08lX ]\n",
> dd->port->flags);
> size += sprintf(&buf[size], "Flag-dd : [ %08lX ]\n",
> @@ -2911,9 +2937,10 @@ static ssize_t mtip_hw_read_flags(struct file *f, char __user *ubuf,
> *offset = size <= len ? size : len;
> size = copy_to_user(ubuf, buf, *offset);
> if (size)
> - return -EFAULT;
> + rv = -EFAULT;
>
> - return *offset;
> + kfree(buf);
> + return rv ? rv : *offset;
> }
>
> static const struct file_operations mtip_device_status_fops = {
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
>


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/